Treatment of artificial filaments threads, yarns, fabrics, and the like



Patented May 31, 1938 UNHTED STATES TREATMENT UF ARTIFICIAL FILAMENTS.

THREADS, YARNS,

LIKE

memos, Ann 'rna' Henry Dreyfus, London, England 9 Claims.

This invention relates to improvements in the treatment of artificial filaments, threads, yarns, fabrics and the like, and is more particularly directed to the treatment of cellulose ester and 5 ether materials for the purpose of obtaining fabrics or other textile materials of improved handle.

In U. S. applications S. Nos. 746,134 filed 29th September, 1934, and 746,135 filed 29th Septem- 10 her, 1934, and S. Nos. 4,086 and 4,085 both filed January 30, 1935, processes are described wherein inter alia yarns of cellulose acetate or other esters or others of cellulose are subjected to treatment with steam or hot water, particularly under conditions of tension which bring about a stretching of the material, so as to produce crepe fabrics, the treatment with the steam or hot water taking place before the application of the crepe twist or during a single stage crpe twisting oper- 20 ation or during any of the stages of a dior multi-stage crpe twisting operation or between any two stages of a dior multi-stage crepe twisting operation. Further, in U. S. applications S. Nos. 4,510 and 4,511 both died February 25 1, 1935, processes are described for stretching yarns or other materials of cellulose acetate or other cellulose esters or others with the assistance of steam or hot water. I

I have now found that the handle of mate- 30 rials treated by any of the above processes is substantially improved by subjecting the materials to a mild treatment with solvents, swelling agents or softening agents for the substance of the material under treatment. Preferably the treatment is such that the solvent, swelling agent or softening agent does not completely penetrate the materials so that its action is not homogeneous and may be extremely superficial. Thus, the outer layers only may be acted upon by the 40 solvent or other softening agent.

The action of the softening agent may be restricted to the outer layers only of the filaments or other materials under treatment in any suitable way. For example the agent may be ap- 5 plied in small quantities only so that it does not penetrate to the core. Alternatively or in addition, and this is the most important method, the time factor may be utilized to prevent the softening agent from penetrating completely. General- 5 ly I prefer to use agents which are either nonvolatile and/or have a low softening power. The agents of high softening power which have comparatively low volatility appear to be less rapid in penetrating the substance of the material, so

55 that their action may be arrested by removal of the softening agent before complete penetration has taken place. Similarly, substances which are volatile but which have only a low softening power for the material under treatment may be used and may be removed sutnciently rapidly by 5 evaporation to avoid complete penetration. However, Washing of the softening agent from the material is the most effective method of limiting the action of the agent to the outer layers of the material.

As indicated it is advisable, except when empioying substances of low penetrating power, to employ only a limited quantity of the softening agent. Thus, the solvent or softening agent may be applied in the vapour state, though even hereit is advisable to treat the materials only for a short time.

The process of the invention may be applied to the treatment of filaments, threads, yarns or other materials made of or containing cellulose derivatives, as for instance cellulose acetate, and particularly acetone-soluble cellulose acetate, cellulose formate, cellulose propionateor butyrate or other esters or mixed esters, and methyl, ethyl, butyl and benzyl celluloses, or othercellulose ethers or mixed ethers and also mixed etheresters, for instance ethyl cellulose acetate. and oxyethyl cellulose acetate. Examples of the swelling agents which may be employed are thiocyanates, zinc chloride, lower aliphatic acids, for example lactic acid and the like, ketones, for instance methyl-ethyl ketone, esters, for instance ethyl lactate, diethyl tartrate and the like, the ethers, including cyclic ethers, esters and etheresters of olefine or polyolefine glycols or glycerinc, e. g. glycol monoacetate, methyl or ethyl glycol monoacetate and the like, chlorinated hydrocarbons, as for instance tetrachlorethane, trichlorethylene, dichlorethylene and the like, phenols, certain alcohols, e. g. ethyl alcohol, etc. Moreover, liquids which at normal temperatures have no softening action or substantially no softening action but which at higher temperatures have such action may be employed at temperatures above atmospheric temperature. Examples of such liquids are glycols, glycerine and Turkey red oil.

Thus for example a very short treatment with cold dilute formic acid or acetic acid followed by removal of the softening agent is very effective for the purpose of the present invention since by such treatment the handle of the goods is substantially improved, and in particular they are much softer to the touch. Thus for instance the goods may be padded with a 10% aqueous solution of formic or acetic acid, given a short air run, and the acid immediately washed off, for example by thorough washing in water at a temperature of the order of 60 to 80 C. The speed of the materials and the length of passage through the padding mangle and the length of the air run may be adjusted so that the total time during which the materials are in contact with the acid is less than a minute, and is preferably half a minute or even less. Alternatively, less powerful softening agents may be employed, as for example a 70 to 80% aqueous solution of methylated spirit or an 80% solution of tetrachlorethane in toluene. In all cases however it is desirable to limit the time during which the materials are in contact with the softening agents so that penetration is limited to the outer layers only.

The treatment in accordance with the present invention may be so conducted that the final filaments are lustrousin appearance or have a medium or quite dull lustre. If the treatmentis carried out so that on removal of the softening medium the concentration of the solvent in the medium decreases, then a dull lustre may result from the present treatment, while if the concentration remains about the same or increases, then the lustre may be maintained or even increased.

The treatment in accordance with the present invention may be carried out so that a slight stretch is applied to the filaments during the solvent treatment.

The solvent treatment may be applied to the materials at any suitable stage after they have been subjected to the stretching and/0r crepe twisting in the presence of steam, hot water or the like. Thus the solvent treatment may he applied before the yarn is formed into fabrics.

Preferably, howeventhe solvent treatment may be applied subsequent to fabric formation and subsequent to the development of the crepe fig ure. "I'he invention doesjhowev'er, include the solvent treatment of materials which, have been stretched'in thepresenceiof steam or hot water or similar agentsquite apart from the production of crepe fabrics.

'rn following, assassinate without in any w'ayliiniting the'inventionz Examplcl A fab'ric' comprisin'glcellulose acetate yarns in the warp-and weft, the weft yarns having been treated with steam and given a crepe twist as described in U. S. applications S. Nos. 746,134 and 746,135, is scoured or otherwise treated to produce a crepe'figure. The crepe fabric resulting is padded with 10% aqueous formic or acetic acid. 'After about 30 seconds the acid is removed from the fabric by thoroughly and rapidly washing with water at a temperature of about 70 C.

Example 2 A dry spun cellulose acetate yarn is stretched as described in Example 2 and, while still wet, is passed at a speed of 20 metres per minute over a heated roller running in diethylene glycol at a temperature of 105 C. The yarn is then passed over a wick, pad or other wiping device, washed substantially free from diethylene glycol and dried.

Example 4 The cellulose acetate crepe fabric of Example 1 is subjected to the mild softening treatment there described except that in place of the acid solutions a 10% solution of glycol monoacetate is employed.

What I claim and desire to secure by Letters Patent is:

1. Process for improving the handle of textilematerials comprising cellulose derivative yarns which have been subjected to a crepe twisting operation in the presence of steam or hot water, which comprises treating the materials with a swelling agent for the cellulose derivative for a very short period, and removing the agent from the materials after it has penetrated the outer layers only of the filaments contained in the yarns.

2. Process for improving the handle of textile materials comprising cellulose acetate yarns which have been subjected to a crepe twisting operation in the presence of steam or hot water, which comprises treating the materials with a swelling agent for the cellulose acetate for a very short period, and removing the agent from the materials after it has penetrated the outer layers only of the filaments contained in the yarns.

3. Process for improving the handle of textile materials comprising cellulose acetate yarns which have been subjected to a crepe twisting 4. Process for improving'the' handle of textile materials comprising cellulose. acetate. yarns whichhave been subjected to a crepe twisting operation in thepresenceof steam or hot ;water,

which comprises subjectingthe filaments con 0 tained inthe yarns to the action of an agent having only 'a slight swelling action on the cellulose acetate for a periodless than two minutes so that penetration is limited. to the outer layers only and then removing the swelling agent.

5. Process for improving the handle of textile materials comprising cellulose acetate yarns which have been subjected to a crepe twisting operation in the presence of steam or hot water, which comprises treating the materials with a relatively non-volatile agent having at least a softening action on the cellulose acetate for a very short period, and removing the agent from the materials after it has penetrated the outer layers only of the filamentscontained in the yarns.

6. Process for improving the handle of textile materials comprising cellulose acetate yarns which have been subjected to a crepe twisting operation in the presence of steam or hot water, which comprises treating the materials with an agent having only a slight swelling action on the cellulose acetate for a very short period, and removing the agent from the materials after it has penetrated the outer layers only of the filaments contained in the yarns.

7. Process for improving the handle of textile 'materials comprising cellulose acetate yarns which have been subjected to a crepe twisting operation in the presence of steam or hot water, which comprises treating the materials with a dilute lower fatty acid in the cold for a period of less than one minute, and then washing the materials free from the acid.

8. Process for improving the handle of textile materials comprising cellulose acetate yarns which have been subjected to a crepe twisting operation in the presence of steam or hot water, and of tentile materials comprising cellulose acetate yarns which have been stretched in the presence of steam or hot water, which comprises treating the materials with a dilute solution of a chlorinated lwdrocarhon having at least a strong swelling action on the cellulose acetate tor a short period so that penetration is limited to the outer layers only, and then removing the solution from the materi W 9. es for improving the handle of textile materials comprising cellulose acetate yarns which have n subjected to a crepe twisting operation in the presence of steam or hot water. which comprises treating the materials with a composition having a swelling action on the cellulose acetate and comprising a glycol ester of a lower fatty acid, and removing the composition by we after it has penetrated the outer le ers only oi the aments con l'l i in the yarns.

CERTIFICATE OF CORRECTION. Patent No. 2,11 ,8 9., May 1, 19 8.

"HENRY DREYFUS.

It'is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page; 2, secondcolumn, lines 61 and 62, claim 5, for the words "agent having at least a softening action on" read: swelling agent for; page}, first column, line's 12 to 15 inclusive," claim 8, strike out the words and comma "and of tex tile materials comprising cellulose-acetate yarns whichhave been stretched in the presence of steam or hot water}; and that the said Letters Patent should he read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 2nd day of August, A. D. 1958.

Leslie Frazer,

S eal) Acting Commissionerof Patents. 

